Energy source system having multiple energy storage devices

ABSTRACT

System are described that include an energy storage device adapted to store and release energy and an ultracapacitor. The systems include a switching device coupled to the energy storage device to selectively connect and disconnect the energy storage device to a load, and a second switching device coupled to the ultracapacitor and adapted to connect and disconnect the ultracapacitor to the load. The systems may include a sensor adapted to sense the current draw at the load. The first switching device is activated to connect the energy storage device to the load when a rate of change of the current draw at the load is below a threshold, and the second switching device is activated to connect the ultracapacitor to the load when the rate of change of the current draw at the load is greater than or equal to the threshold.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a Non-Provisional Application of U.S. ProvisionalPatent Application No. 61/453,474, entitled “Combined Battery and SuperCapacitor Systems for Vehicle Applications,” filed Mar. 16, 2011, andU.S. Provisional Patent Application No. 61/508,621, entitled “System forStorage of Charge and Energy with an Integrated Controller,” filed Jul.16, 2011, and U.S. Provisional Patent Application No. 61/477,730,entitled “Multiple Battery System for Vehicle Applications,” filed Apr.21, 2011, and U.S. Provisional Patent Application No. 61/508,622,entitled “Differential State of Charge Battery for Improved ChargingCapability,” filed Jul. 16, 2011, which are herein incorporated byreference.

The present patent application is generally related to the followingco-pending patent applications, which are hereby incorporated into thepresent application by reference: U.S. application Ser. No. 13/422,246,entitled “Energy Source Systems Having Devices with Differential Statesof Charge”, filed by Ou Mao et al. on Mar. 16, 2012; U.S. applicationSer. No. 13/422,326, entitled “Systems and Methods for ControllingMultiple Storage Devices”, filed by Brian C. Sisk et al. on Mar. 16,2012; U.S. application Ser. No. 13/422,421, entitled “Energy SourceDevices and Systems Having a Battery and An Ultracapacitor”, filed byPerry M Wyatt et al. on Mar. 16, 2012; and U.S. application Ser. No.13/422,621, entitled “Systems and Methods for Overcharge Protection andCharge Balance in Combined Energy Source Systems”, filed by Junwei Jianget al. on Mar. 16, 2012.

FIELD

The presently disclosed embodiments relate generally to energy sourcesystems capable of providing energy for a downstream application. Morespecifically, presently disclosed embodiments relate to energy sourcesystems including combined battery and ultracapacitor devices forvehicle applications. Still more specifically, presently disclosedembodiments relate to a combined battery and ultracapacitor system thatmeets all of the electrical demands for vehicle loads, includingstarting, lighting and ignition, in a package that occupies less spaceand with less weight than conventional vehicle battery systems.

BACKGROUND

This section is intended to provide a background or context to theinvention recited in the claims. The description herein may includeconcepts that could be pursued, but are not necessarily ones that havebeen previously conceived or pursued. Therefore, unless otherwiseindicated herein, what is described in this section is not prior art tothe description and claims in this application and is not admitted to beprior art by inclusion in this section.

It is generally known to provide typical Pb-acid batteries for starting,lighting, and ignition (SLI) applications in a vehicle. Such Pb-acidbatteries usually have a capacity of about 70 Ah and a voltage of about12V. The weight of such Pb-acid batteries is typically about 21 kg andthe energy density is often about 40 Wh/kg. One performance requirementfor such Pb-acid batteries for SLI applications is referred to as the“cold cranking current,” which is about 700 Ah at (−)18° C. Such a highcold cranking current requirement is for the vehicle engine startingpurpose, for delivery within a few seconds, especially under coldweather conditions. However, such known Pb-acid batteries, in order tomeet the cold cranking current requirement, are sized such that theytend to occupy a relatively large amount of space, and add a significantamount of weight to the vehicle platform.

Another drawback with conventional battery systems is the issue of poorcharge acceptance. That is, in certain instances, the battery may not becapable of handling the high charge current, which may have anundesirable impact on the vehicle's energy regeneration capability.Accordingly, it would be desirable to provide one or more advancedenergy source systems that are capable of efficiently meeting the coldcranking current requirements for engine starting while being packagedin a smaller and lighter device. Further, it would also be desirable toprovide one or more advanced energy source systems that are adaptablefor use with components associated with start-stop technology orcomponents of the vehicle (e.g. to permit stopping of the vehicle engineduring standstill periods and restart upon demand by the driver), orwith components associated with mild-hybrid technology or components ofthe vehicle (e.g. to provide motor-driven boost or assist inaccelerating a vehicle to a cruising speed), and electrical vehicleapplications, and in a voltage range of approximately 10-400V, and moreparticularly within a range of approximately 10-100V.

SUMMARY

In one embodiment, a system includes an energy storage device adapted tostore and release energy and an ultracapacitor. The system also includesa first switching device coupled to the energy storage device andadapted to selectively connect and disconnect the energy storage deviceto a load and a second switching device coupled to the ultracapacitorand adapted to selectively connect and disconnect the ultracapacitor tothe load. The system also includes a current sensor adapted to sense thecurrent draw at the load. The first switching device is adapted to beactivated to connect the energy storage device to the load when a rateof change of the current draw at the load is below a preset threshold,and the second switching device is adapted to be activated to connectthe ultracapacitor to the load when the rate of change of the currentdraw at the load is greater than or equal to the preset threshold.

In another embodiment, a method includes monitoring a parametercorresponding to a demand present at a load and determining, based on arate of change of the monitored parameter over time, whether the rate ofchange of the monitored parameter is greater than or equal to a presetthreshold. The method also includes controlling a first switch to couplea battery to the load when the rate of change of the monitored parameteris not greater than or equal to the preset threshold. Further, themethod includes controlling a second switch to couple an ultracapacitorto the load when the rate of change of the monitored parameter isgreater than or equal to the preset threshold.

In another embodiment, a system includes a battery having one or moreelectrochemical cells coupled in series with one another and anultracapacitor. The system also includes a first switching devicecoupled to the battery and adapted to selectively connect and disconnectthe battery to a load and a second switching device coupled to theultracapacitor and adapted to selectively connect and disconnect theultracapacitor to the load. The system also includes a direct current todirect current (DC-DC) converter adapted to electrically couple thebattery to the ultracapacitor and a sensing system adapted to sense anoperational parameter of the battery, an operational parameter of theultracapacitor, and a load parameter. Further, the system includes acontroller coupled to the first switching device, the second switchingdevice, and the DC-DC converter and adapted to determine, based on thesensed operational and load parameters, an energy flow between thebattery, the ultracapacitor, the DC-DC converter, and the load and tocontrol the first switching device, the second switching device, and theDC-DC converter to achieve the determined energy flow.

In another embodiment, a method includes detecting an engine startsignal and determining, based on a received input, if the energy storedin a battery is sufficient to start an internal combustion engineassociated with an electromechanical vehicle. The method also includescontrolling a direct current to direct current (DC-DC) converter totransfer energy from the battery to an ultracapacitor when the energystored in the battery is not sufficient to start the internal combustionengine. Further, the method includes controlling a switch coupled to theultracapacitor to electrically couple the ultracapacitor to the internalcombustion engine to enable a flow of energy from the ultracapacitor tothe internal combustion engine to start the internal combustion energywhen the energy stored in the battery is not sufficient to start theinternal combustion engine.

In another embodiment, a controller is adapted to detect an engine startsignal and to determine, based on a received input, if the energy storedin a battery is sufficient to start an internal combustion engineassociated with an electromechanical vehicle. The controller is alsoadapted to control a direct current to direct current (DC-DC) converterto transfer energy from the battery to an ultracapacitor when the energystored in the battery is not sufficient to start the internal combustionengine. Further, the controller is adapted to control a switch coupledto the ultracapacitor to electrically couple the ultracapacitor to theinternal combustion engine to enable a flow of energy from theultracapacitor to the internal combustion engine to start the internalcombustion energy when the energy stored in the battery is notsufficient to start the internal combustion engine.

DRAWINGS

The disclosure will become more fully understood from the followingdetailed description, taken in conjunction with the accompanyingfigures, wherein like reference numerals refer to like elements, inwhich:

FIG. 1 illustrates an electrical supply system having a negativeterminal and a positive terminal disposed on a housing that encloses anenergy storage device and an ultracapacitor in accordance with anembodiment;

FIG. 2 is a schematic representation of a battery and ultracapacitordesign for vehicle applications according to one embodiment of thesystems described herein;

FIG. 3 illustrates an embodiment of a circuit that may be utilized toelectrically couple an energy storage device and an ultracapacitorwithin a housing having two terminals in accordance with an embodiment;

FIG. 4 illustrates an embodiment of a circuit that may be utilized toelectrically couple an energy storage device and an ultracapacitorutilizing at least one variable resistance device in accordance with anembodiment;

FIG. 5 illustrates an embodiment of a method that may be implemented bya controller to utilize sensed feedback to intelligently controloperation of a multiple device system in accordance with an embodiment;

FIG. 6 illustrates an embodiment of a circuit that may be utilized toelectrically couple an energy storage device, an ultracapacitor, and aDC/DC converter within a housing having two terminals in accordance withan embodiment;

FIG. 7 illustrates an embodiment of a safe start method that may beimplemented by a controller to control a battery and an ultracapacitorin accordance with an embodiment;

FIG. 8 is a schematic representation of a battery and ultracapacitordesign for vehicle applications according to a first embodiment of thesystems described herein;

FIG. 9 is a schematic representation of a battery and ultracapacitordesign for vehicle applications according to a second embodiment of thesystems described herein;

FIG. 10 is a schematic representation of a battery and ultracapacitordesign for vehicle applications according to a third embodiment of thesystems described herein;

FIG. 11 is a schematic representation of a battery and ultracapacitordesign for vehicle applications according to a fourth embodiment of thesystems described herein;

FIG. 12 is a schematic representation of a battery and ultracapacitordesign for vehicle applications according to a fifth embodiment of thesystems described herein;

FIG. 13 is a schematic representation of a battery and ultracapacitordesign for vehicle applications according to a sixth embodiment of thesystems described herein;

FIG. 14 is a schematic representation of a battery and ultracapacitordesign for vehicle applications according to a seventh embodiment of thesystems described herein;

FIG. 15 is a schematic representation of a battery and ultracapacitordesign for vehicle applications according to an eighth embodiment of thesystems described herein;

FIG. 16 illustrates an energy source system including a differentialstate of charge (SOC) energy storage device having a housing thatencloses a low SOC energy storage device and a high SOC energy storagedevice in a single enclosure in accordance with an embodiment;

FIG. 17 illustrates an embodiment of voltage versus state of charge(SOC) curves for energy storage devices having different states ofcharge in accordance with an embodiment;

FIG. 18 illustrates an embodiment of voltage versus state of charge(SOC) curves for energy storage devices having different states ofcharge in accordance with an embodiment;

FIG. 19 illustrates a power capability advantage that may be gained bycombining a low state of charge (SOC) device and a high SOC device in asingle package in accordance with an embodiment;

FIG. 20 illustrates a power capability advantage that may be gained bycombining a low state of charge (SOC) device and a high SOC device in asingle package in accordance with an embodiment;

FIG. 21 illustrates an embodiment of a standard battery enclosure thatis internally configured to house one or more batteries or cells and oneor more ultracapacitors;

FIG. 22 illustrates an embodiment of a battery enclosure havingdimensions that conform and a unique shape that may conform to those ofa desired battery that the new assembly and circuitry are intended toreplace;

FIG. 23 is perspective view of an embodiment of a vehicle having abattery module or system for providing all or a portion of the motivepower for the vehicle; and

FIG. 24 illustrates a cutaway schematic view of an embodiment of thevehicle of FIG. 23 provided in the form of a hybrid electric vehicle.

DETAILED DESCRIPTION

In accordance with presently disclosed embodiments, provided herein areadvanced battery and ultracapacitor systems having overcharge protectionand charge balancing capabilities. In some embodiments, the high powerdischarge capability of the ultracapacitors may be utilized to meet thecold cranking current requirements for a vehicle engine start, and asmaller and lighter battery may be utilized to provide the energy forother vehicle electrical applications. According to any of theillustrated embodiments, the vehicle applications may include one ormore of internal combustion engines, hybrid, micro-hybrid, start-stopand electric vehicle applications, and may include voltage applicationswithin the range of approximately 10V to approximately 400V, and moreparticularly, within a range of approximately 10V and approximately100V. Although only a certain number of battery types have beendescribed in the illustrated embodiments by way of example, any of awide variety of other battery types and chemistries may be adapted foruse with ultracapacitors for use in providing a smaller and/or lighterelectrical power supply for a wide variety of vehicle applications.Accordingly, all such variations are intended to be within the scope ofthis disclosure.

One type of battery technology suitable for use with the systemsdescribed herein in Li-ion technology. The Li-ion battery technologyprovides a relatively high energy density up to about 200 Wh/kg, whichis generally about five times that of the Pb-acid battery energydensity. Thus, there are benefits for using Li-ion battery technology insome embodiments to replace the conventional Pb-acid battery for SLIapplications in vehicles, such as (by way of example, and not limitedto) elimination of Pb toxic compounds, lighter weight, and smaller spacerequirements. However, the cold cranking performance of Li-iontechnology, by itself, is generally understood to limit the use ofLi-ion technology in such applications. A typical Li-ion batterydischarge rate at (−)18° C. is generally about a 2 C rate, where 2 Crate represents a discharge current of about 140 A for 70 Ah batteries,which is lower than the typical Pb-acid battery cold crankingperformance (around 10 C rate).

Turning now to the drawings, FIG. 1 illustrates an electrical supplysystem 10 having a housing 12 with a negative terminal 14 that isconnected to ground 16 and a positive terminal 18 that is capable ofbeing coupled to an implementation-specific vehicle connection 20, suchas a switch, a starter motor, etc. As shown, an energy storage device 22and an ultracapacitor 24 are provided within the housing 12. That is, asingle housing 12 having two terminals 14 and 18 encloses both theenergy storage device 22 and the ultracapacitor 24. The foregoingfeature may enable the electrical supply system 10 to be dimensioned insuch a way that enables the system 10 to be utilized to replace avariety of battery devices having standardized dimensions, for example,a standard 12V battery. As such, it should be noted that the housing 12and the configuration of the terminals 14 and 18 may be susceptible to avariety of implementation-specific variations in size, shape, andplacement, as discussed in more detail below. For example, in certainembodiments the system may be designed such that the housing orenclosure is configured to permit simple and direct replacement ofexisting battery systems, such as conventional vehicular batteries. Assuch, the enclosure may conform to standard sizing and form factors,particularly relating to the length, width, and height of the enclosure,the placement of terminals, the configuration of the terminals, theplacement and dimensions of features intended to hold the battery systemin place, and so forth. Where desired, the actual enclosure may besomewhat smaller than such conventional form factors, and adapters,shims and similar structures may be used to allow for such replacement.Such adapters and structures may also allow for the use of enclosures ofirregular or non-standard shapes. In either case, there may be need forlittle or no change in the supporting and interfacing structures of thevehicle or other application in which the system is placed as comparedto current structures.

It should be noted that, as will be appreciated by those skilled in theart, distinctions exist between “charge” and “energy”, both physicallyand in terms of unitary analysis. In general, charge will be stored andenergy converted during use. However, in the present context, the twoterms will often be used somewhat interchangeably. Thus, at timesreference is made to “charge storage” or to “the flow of charge”, or tosimilar handling of “energy”. This use should not be interpreted astechnically inaccurate or limiting insomuch as the batteries,ultracapacitors, and other devices and components may be said, in commonparlance, to function as either energy storage devices or charge storagedevices, and sometimes as either or both.

Further, as shown in the illustrated embodiment, the housing 12 alsoencloses a controller 26 that is coupled to the energy storage device 22and the ultracapacitor 24 and may control operation of the multipledevice system. It should be noted that the controller 26 shown in FIG. 1may be any controller that is suitable for use with a multiple devicesystem. However, in some presently contemplated embodiments, the energystorage device 22 and the ultracapacitor 24 may be controlled by amultiple device controller such as the controller described in theco-pending application entitled “SYSTEMS AND METHODS FOR CONTROLLINGMULTIPLE STORAGE DEVICES,” which is hereby incorporated by reference, aspreviously mentioned.

Further, it should be noted that the energy storage device 22 and theultracapacitor 24 in FIG. 1 are merely illustrative, and each device mayinclude one or more devices in other embodiments. For example, referringgenerally to the embodiment illustrated in FIG. 2, a combination ofLi-ion technology with an ultracapacitor pack may provide an improvedvehicle electrical power system, since the high power ultracapacitor canquickly discharge with high power to start the vehicle engine (e.g.,within approximately 2 or 3 seconds). More specifically, FIG. 2illustrates one embodiment of the design of the combination of a Li-ionbattery 28 having four cells 30, 32, 34, and 36 (each with a capacity ofapproximately 15 Ah) and a bank 38 of ultracapacitors 40, 42, 44, 46,48, and 50 (each with a capacity of about 2000 Farads and 2.7 VDC). Inone embodiment, the average voltage of each Li-ion battery cell(LiFePO4/graphite) is about 3.3V, and thus, the four cell pack in seriesprovides a voltage of about 13.2V. The six ultracapacitors 40, 42, 44,46, 48, and 50 in series provide an average voltage of about 12V.

Further, during cold cranking current requirements, the ultracapacitorpack 38 can supply a maximum current of about 2,000 Amps within 2seconds at cold temperatures around (−)18° C., which is generallyunderstood to be sufficient to start a vehicle engine. Further, thetotal weight of such a four cell Li-ion battery and six ultracapacitorpack is about seven 7 kg, compared to a weight of about 21 kg for aPb-acid battery with a capacity of about 70 Ah for vehicle starting,lighting, and ignition (SLI) applications. The maximum power for such aLi-ion and ultracapacitor system reaches to about 46 kW, compared toabout 5.6 kW for the Pb-acid battery pack (70 Ah) at low temperatures ofabout (−)18° C.

FIGS. 3 and 4 illustrate additional embodiments of circuits 52 and 54that may be utilized to electrically couple an embodiment of the energystorage device 22 and an embodiment of the ultracapacitor 24 forpackaging in the housing 12 having two terminals 14 and 18.Specifically, in the illustrated embodiments, a battery 56 and acapacitor 58, which may be an ultracapacitor in certain embodiments, arecoupled to a current sensor 60. In the embodiment of FIG. 3, the battery56 is electrically coupled to the positive terminal 18 via a firstswitch 62, and the capacitor 58 is electrically coupled to the positiveterminal 18 via a second switch 64. However, it should be noted that theswitches 62 and 64 illustrated in FIG. 3 may, in other embodiments, bevariable resistance devices capable of feathering in and out theassociated device, for example, as dictated by the controller 26. Forinstance, in the embodiment of FIG. 4, the second switch 64 is afield-effect transistor (FET) 66 capable of being controlled to connectand disconnect the capacitor 58 to a load present at the positiveterminal 18 in a variable manner. Additionally, it should be noted thatin other embodiments, the first switch 62 may also be a variableresistance device, such as a FET.

During operation, the current sensor 60 senses the current draw presentat the load, thus enabling the controller 26 to determine, based on thesensed level, the nature of the load that is present. For example, thecurrent sensor 60 may sense a level that corresponds to an accessorydrain or alternatively, the current sensor 60 may sense a level thatcorresponds to a power draw. The controller 26 may then utilize thesensed current level to determine which of the battery 56 and thecapacitor 58 should be activated, for example, via closing of theswitches 62 and 64. For example, if an accessory drain from a vehicle isdetected at the load, the switch 62 may be closed, thus enabling thebattery 56 to meet the accessory demand. For further example, if a powerdraw, such as a draw associated with starting of an internal combustionengine, is detected, the switch 64 may be closed to enable the capacitor58 to meet the power draw. Still further, in some embodiments, thecontroller may control the FET 66 and a FET coupled to the battery 56such that the load is met by a combination of power delivered from thedevices 56 and 58. Accordingly, presently disclosed embodiments mayprovide for sensing a parameter of the load and intelligentlycontrolling the devices 56 and 58 to meet the demand present at theload.

FIG. 5 illustrates an embodiment of a method 68 that may be implementedby, for example, the controller 26, to utilize the sensed feedback tointelligently control operation of the multiple device system. Once theoperation is started (block 70), the controller 26 receives an initialvalue for the current draw level (block 72), for example, from thecurrent sensor 60, and then receives a present value of the current drawat a later time point (block 74). In this embodiment, the method 68proceeds with an inquiry as to whether the rate of change of the currentdraw with respect to time is greater than or equal to a preset threshold(block 76). If the rate of change of the sensed current meets or exceedsthe given threshold, the controller 26 activates the capacitor 58 tomeet the demand (block 78). For example, the controller may utilizeswitch 64 to couple the capacitor 58 to the load present at the positiveterminal 18. However, if the rate of change of the sensed current isbelow the preset threshold, the battery 56 is activated to meet thedemand at the load (block 80).

In this way, the rate of change of sensed current over time may beutilized to determine which of the devices 56 and 58 are utilized tomeet the demand of the load. It should be noted that although the sensorin the illustrated embodiment is a current sensor, in other embodiments,any suitable sensor or combination of sensors capable of sensing a loadparameter may be utilized. Additionally, any suitable indicator, notlimited to the rate of change of current with respect to time, may beutilized to determine which device is activated to meet the demand atthe load. Still further, in certain embodiments, a variety of thresholdsor inquiries may be utilized to determine which portion of the loadshould be met by each device. That is, in certain embodiments, thecontroller may utilize additional logic to determine an appropriateshared distribution of the load between the devices.

FIG. 6 illustrates an additional embodiment of a circuit 82 that may beutilized to electrically couple the battery 56 and the capacitor 58 tothe load present at the positive terminal 18. In this embodiment, asbefore, the switches 62 and 64 couple the battery 56 and the capacitor58, respectively, to the positive terminal 18. However, as shown, thecircuit 82 includes a direct current to direct current (DC/DC) converterthat electrically couples the battery 56 and the capacitor 58. Further,a sensing system 85 includes a battery voltage sensor 86, a capacitorvoltage sensor 88, and a net voltage sensor 90 capable of measuring thevoltage of the battery, the voltage of the capacitor, and the netvoltage, respectively, throughout operation of the circuit 82.

During operation of the circuit 82, the sensing system 85 may beutilized to measure voltage levels at a variety of locations in thecircuit 82, thus enabling the controller 26 to acquire informationregarding both load requirements as well as the quantity of energy eachof the devices 56 and 58 is capable of providing. Therefore, based onthe information received from the sensing system 85, the controller 26may control the switches 62 and 64 and the DC/DC converter 84 to meetthe demand at the load in accordance with energy available from each ofthe devices 56 and 58 at any given operational time point. Further, itshould be noted that, as before, the switches 62 and 64 may be variabledevices, such as FETs, that enable the controller to feather in and outeach of the devices as appropriate.

In one embodiment, the circuit 82 of FIG. 6 may be packaged, forexample, within housing 12, with the controller 26 and utilized in placeof a traditional vehicle battery. In such an embodiment, the circuit 82,operated under control of the controller 26, may be utilized to reduceor eliminate the likelihood that the vehicle in which the device 10 isplaced is unable to start when the voltage of the battery 56 is drainedbelow a level sufficient to start, for example, the internal combustionengine of the vehicle. Here again, it should be noted that, as discussedin more detail below, the housing 12 and the configuration of theterminals 14 and 18 may be dimensioned and configured for the vehicle inwhich the device 10 is intended to be utilized.

FIG. 7 illustrates an embodiment of a method 92 that may be implementedby the controller 26 to ensure that a vehicle with which the circuit 82is associated is started if possible given the energy available in thedevices 56 and 58. Once the operation is started (block 94), an operatordemand to start the vehicle is detected (block 96). For example, theoperator may insert and turn a key in a console of the vehicle, press abutton to start the vehicle, and so forth, depending on the specificvehicle type. In some embodiments, the battery 56 may be designated asthe primary energy source that is to be utilized for routine vehiclestarting events. In such embodiments, at certain times, the voltage ofthe battery may be too low to support an engine start event, and thecontroller 26 receives an input indicating that the available voltagefrom the battery is insufficient to meet the operator demand to startthe vehicle (block 98).

In such instances, presently disclosed embodiments provide for a reducedor prevented likelihood that battery drainage will prohibit the vehiclefrom being started. More specifically, the method 92 includes the stepof controlling the DC/DC converter 84 to utilize the available voltagein the battery 56 to charge the capacitor 58 (block 100). That is,although the voltage in the battery 56 may be insufficient to start thevehicle, the available voltage may be sufficient to charge the capacitor58. Once the vehicle fails to start upon the operator's first request,the operator may again attempt to start the vehicle, and the controller26 detects this demand (block 102). Since the capacitor 58 was chargedduring the time lapse between the first start attempt and the secondstart attempt, the capacitor 58 may be utilized to start the vehicle(block 104), thus fulfilling the operator request. In this way, thecircuit 82 may be controlled to reduce or prevent the likelihood thatthe vehicle will not be able to start when the battery voltage is low,thus offering advantages over traditional systems that may utilize abattery in place of the multiple device system 10.

FIGS. 8-15 illustrate additional embodiments of circuits includingvarious combinations of batteries, ultracapacitors, overchargeprotection circuits, and charge balancing circuits. Specifically, FIG. 8illustrates an embodiment of a combined battery and ultracapacitorsystem 106 for vehicle applications with recharge capability. The system106 as shown in FIG. 8 includes a battery 108 having a number of cells(or battery units) C1, C2, . . . CX that are connected in series and toterminals T3 (110) and T4 (112), which are connected to the alternatorof the vehicle's electrical system for maintaining the charge on thebattery cells 108 (and providing a power source to other electricalloads of the vehicle). An ultracapacitor pack 114 is shown connected inparallel with the battery 108 and has individual ultracapacitors S1, S2,. . . SY connected in series with one another and to terminals T1 (116)and T2 (118), which are connected to the engine-starting portion of thevehicle's electrical system for providing relatively short and highcurrent for starting the vehicle. The number of ultracapacitors and thecapacity of the ultracapacitors are selected so that the total voltageof the ultracapacitors 114 substantially matches the total voltage ofthe series of cells in the battery 108. The system 106 also includes amanagement and control system 120 that permits the battery 108 toquickly recharge the ultracapacitors 114 following discharge (e.g.engine starts).

According to the illustrated embodiment, the management and controlsystem 120 includes first management and control circuitry 122 that isassociated with the ultracapacitors 114, as well as second managementand control circuitry 124 that is associated with the battery 108.During operation, the management and control system 120 operates toprovide overcharge protection and charge balance for the ultracapacitors114. As such, it should be noted that the first control circuitry 122and the second control circuitry 124 may communicate with one another,for example, via a wired or wireless connection, to coordinate operationof the battery 108 and the ultracapacitors 114. Further, in certainembodiments, the management and control system 120 monitors, controls,and balances the battery 108 and the ultracapacitors 114. As such,during operation, the functions of the management and control system 120may include, but are not limited to monitoring parameters of the batteryand ultracapacitors (e.g., voltage, temperature, state ofcharge/discharge, state of health, current, etc.), computing desiredparameters (e.g., maximum charge/discharge current, total energydelivery, total operating time, etc.), communicating with systemcomponents (e.g., via CAN bus, wireless communication, etc.), providingprotection capabilities (e.g., over-current, over-charge/dischargevoltage, over/under temperature, etc.), and balancing to enable thefunction of energy storage system.

More specifically, during operation, the control circuitry 122 and 124controls the flow of energy between the battery 108 and theultracapacitors 114 to permit current flow only in the direction fromthe battery 108 to the ultracapacitors 114. Further, the first controlcircuitry 122 is coupled to each ultracapacitor to provide overchargeprotection and balancing of the charge among the ultracapacitors ascurrent flows from the battery 108 to the ultracapacitors 114. Forexample, in some embodiments, the control circuitry 122 may control thecurrent flow such that as the flow from the battery 108 reaches eachultracapacitor (from S1 to Sy), current is directed first to S1, then toS2 and so on, until the current reaches Sy. In this way, when eachultracapacitor reaches its required voltage level, the current from thebattery 108 will bypass that ultracapacitor to balance with the otherultracapacitors in the pack 114. According to other embodiments, othercomponents or devices may be used to balance the charging of theultracapacitors; all such variations are intended to be within the scopeof this disclosure.

FIG. 9 illustrates a combined 12V Pb-acid battery and ultracapacitorsystem 128 for vehicle applications with recharge capability, accordingto a presently disclosed embodiment. The system 128, as shown in FIG. 9includes a battery 130 having a number of cells (or battery units) shownas six cells C1, C2, C3, C4, C5 and C6 that are connected in series withone another and to terminals T3 (110) and T4 (112), which are connectedto the alternator of the vehicle's electrical system for maintaining thecharge on the battery cells (and providing a power source to otherelectrical loads of the vehicle). An ultracapacitor pack 132 is shownconnected in parallel with the battery 130 and has six individualultracapacitors S1, S2, S3, S4, S5 and S6 connected in series with oneanother and to terminals T1 (116) and T2 (118), which are connected tothe engine-starting portion of the vehicle's electrical system forproviding relatively short and high current for starting the vehicle.The number of ultracapacitors and the capacity of the ultracapacitorsare selected so that the total voltage of the ultracapacitors 132substantially matches the total voltage of the series of cells in thebattery 130. According to the embodiment of FIG. 9, each of the sixPb-acid cells has a voltage of approximately 2V, so that the totalvoltage of the battery is about 12V. Also, each of the sixultracapacitors has an average voltage of about 1.9V (but may be withinthe range of about 1V-2.8V). Accordingly, six ultracapacitors areselected so that the total voltage approximately matches the voltage ofthe Pb-acid battery.

The system of FIG. 9 also includes the management and control system 120that permits the Pb-acid battery 130 to quickly recharge the sixultracapacitors 132 following discharge (e.g. engine starts). As before,in the illustrated embodiment, the management and control system 120includes the first management and control circuitry 122 and the secondmanagement and control circuitry 124. During operation, the managementand control system 120 operates to provide overcharge protection andcharge balance for the ultracapacitors 132. More specifically, duringoperation, the control circuitry 122 and 124 controls the flow of energybetween the Pb-acid battery 130 and the ultracapacitors 132 to permitcurrent flow only in the direction from the Pb-acid battery 130 to theultracapacitors 132.

Further, the first control circuitry 122 is coupled to eachultracapacitor to provide overcharge protection and balancing of thecharge among the ultracapacitors as current flows from the Pb-acidbattery 130 to the ultracapacitors 132. For example, in someembodiments, the control circuitry 122 may control the current flow suchthat as the flow from the Pb-acid battery 130 reaches eachultracapacitor (from S1 to S6), current is directed first to S1, then toS2 and so on, until the current reaches S6. In this way, when eachultracapacitor reaches its required voltage level, the current from thePb-acid battery 130 will bypass that ultracapacitor to balance with theother ultracapacitors in the pack 132. According to other embodiments,other components or devices may be used to balance the charging of theultracapacitors; all such variations are intended to be within the scopeof this disclosure.

Referring to FIG. 10, a combined 13V Li-ion (LiFePO4 cathode/carbonanode) battery and ultracapacitor system 150 for vehicle applicationswith recharge capability is shown according to a presently disclosedembodiment. The system 150, as shown in FIG. 10, includes a battery 152having a number of cells (or battery units) shown as four cells C1-C4that are connected in series with one another and to terminals T3 (110)and T4 (112), which are connected to the alternator of the vehicle'selectrical system for maintaining the charge on the battery cells 152(and providing a power source to other electrical loads of the vehicle).A ultracapacitor pack 132 is shown connected in parallel with thebattery 152 and has six individual ultracapacitors S1, S2, S3, S4, S5and S6 connected in series with one another and to terminals T1 (116)and T2 (118), which are connected to the engine-starting portion of thevehicle's electrical system for providing relatively short and highcurrent for starting the vehicle. As before, the number ofultracapacitors and the capacity of the ultracapacitors are selected sothat the total voltage of the ultracapacitors substantially matches thetotal voltage of the series of cells in the battery. According to theembodiment of FIG. 10, each of the four Li-ion cells has a voltage ofapproximately 3.3V, so that the total voltage of the battery is about13.2V. Also, each of the six ultracapacitors has an average voltage ofabout 1.9V (but may be within the range of about 1V-2.8V). Accordingly,six ultracapacitors are selected so that the total voltage approximatelymatches the voltage of the Li-ion battery.

The system of FIG. 10 also includes the management and control system120 that permits the Li-ion battery to quickly recharge the sixultracapacitors following discharge (e.g. engine starts). In theillustrated embodiment, the management and control system 120 includesthe first management and control circuitry 122 and the second managementand control circuitry 124 that cooperatively operate to provideovercharge protection and charge balance for the ultracapacitors 132.More specifically, during operation, the control circuitry 122 and 124controls the flow of energy between the Li-ion battery 152 and theultracapacitors 132 to permit current flow only in the direction fromthe Li-ion battery 152 to the ultracapacitors 132.

Further, the first control circuitry 122 is coupled to eachultracapacitor to provide overcharge protection and balancing of thecharge among the ultracapacitors as current flows from the Li-ionbattery 152 to the ultracapacitors 132. For example, in someembodiments, the control circuitry 122 may control the current flow suchthat as the flow from the Li-ion battery 152 reaches each ultracapacitor(from S1 to S6), current is directed first to S1, then to S2 and so on,until the current reaches S6. In this way, when each ultracapacitorreaches its required voltage level, the current from the Li-ion battery152 will bypass that ultracapacitor to balance with the otherultracapacitors in the pack 132. According to other embodiments, othercomponents or devices may be used to balance the charging of theultracapacitors; all such variations are intended to be within the scopeof this disclosure.

Referring to FIG. 11, a combined 13V Li-ion (LiMn₂O₄ cathode/Li₄Ti₅O₁₂anode) battery and ultracapacitor system 154 for vehicle applicationswith recharge capability is shown according to an exemplary embodiment.The system as shown in FIG. 11 includes a battery 156 having a number ofcells (or battery units) shown as six cells C1-C6 that are connected inseries with one another and to terminals T3 (110) and T4 (112), whichare connected to the alternator of the vehicle's electrical system formaintaining the charge on the battery cells (and providing a powersource to other electrical loads of the vehicle). The ultracapacitorpack 132 is shown connected in parallel with the battery 156 and has sixindividual ultracapacitors S1, S2, S3, S4, S5 and S6 connected in serieswith one another and to terminals T1 (116) and T2 (118), which areconnected to the engine-starting portion of the vehicle's electricalsystem for providing relatively short and high current for starting thevehicle. The number of ultracapacitors and the capacity of theultracapacitors are selected so that the total voltage of theultracapacitors substantially matches the total voltage of the series ofcells in the battery. According to the embodiment of FIG. 11, each ofthe six Li-ion cells (with a LiMn₂O₄ cathode and a Li₄Ti₅O₁₂ anode) hasa voltage of approximately 2.2V, so that the total voltage of thebattery 156 is about 13.2V. Also, each of the six ultracapacitors has anaverage voltage of about 1.9V (but may be within the range of about1V-2.8V). Accordingly, six ultracapacitors are selected so that thetotal voltage approximately matches the voltage of the Li-ion battery.

The system of FIG. 11 also includes the management and control system120 that permits the Li-ion battery 156 to quickly recharge the sixultracapacitors 132 following discharge (e.g. engine starts). In theillustrated embodiment, the management and control system 120 includesthe first management and control circuitry 122 and the second managementand control circuitry 124 that cooperatively operate to provideovercharge protection and charge balance for the ultracapacitors 132.More specifically, during operation, the control circuitry 122 and 124controls the flow of energy between the Li-ion battery 156 and theultracapacitors 132 to permit current flow only in the direction fromthe Li-ion battery 156 to the ultracapacitors 132.

Further, the first control circuitry 122 is coupled to eachultracapacitor to provide overcharge protection and balancing of thecharge among the ultracapacitors as current flows from the Li-ionbattery 156 to the ultracapacitors 132. For example, in someembodiments, the control circuitry 122 may control the current flow suchthat as the flow from the Li-ion battery 156 reaches each ultracapacitor(from S1 to S6), current is directed first to S1, then to S2 and so on,until the current reaches S6. In this way, when each ultracapacitorreaches its required voltage level, the current from the Li-ion battery156 will bypass that ultracapacitor to balance with the otherultracapacitors in the pack 132. According to other embodiments, othercomponents or devices may be used to balance the charging of theultracapacitors; all such variations are intended to be within the scopeof this disclosure.

Referring to FIG. 12, a combined 12V Li-ion (LiMn_(3/2)Ni_(1/2)O₄cathode/Li₄Ti₅O₁₂ anode) battery and ultracapacitor system 158 forvehicle applications with recharge capability is shown according to apresently disclosed embodiment. The system 158 as shown in FIG. 12includes a battery 160 having a number of cells (or battery units) shownas four cells C1-C4 that are connected in series with one another and toterminals T3 (110) and T4 (112), which are connected to the alternatorof the vehicle's electrical system for maintaining the charge on thebattery cells (and providing a power source to other electrical loads ofthe vehicle). The ultracapacitor pack 132 is shown connected in parallelwith the battery 160 and has six individual ultracapacitors S1, S2, S3,S4, S5 and S6 connected in series with one another and to terminals T1(116) and T2 (118), which are connected to the engine-starting portionof the vehicle's electrical system for providing relatively short andhigh current for starting the vehicle. The number of ultracapacitors andthe capacity of the ultracapacitors are selected so that the totalvoltage of the ultracapacitors substantially matches the total voltageof the series of cells in the battery. According to the embodiment ofFIG. 12, each of the four Li-ion cells (with a LiMn_(3/2)Ni_(1/2)O₄cathode and a Li₄Ti₅O₁₂ anode) has a voltage of approximately 3V, sothat the total voltage of the battery is about 12V. Also, each of thesix ultracapacitors has an average voltage of about 1.9V (but may bewithin the range of about 1V-2.8V). Accordingly, six ultracapacitors areselected so that the total voltage approximately matches the voltage ofthe Li-ion battery.

The system of FIG. 12 also includes the management and control system120 that permits the Li-ion battery 160 to quickly recharge the sixultracapacitors following discharge (e.g. engine starts). In theillustrated embodiment, the management and control system 120 includesthe first management and control circuitry 122 and the second managementand control circuitry 124 that cooperatively operate to provideovercharge protection and charge balance for the ultracapacitors 132.More specifically, during operation, the control circuitry 122 and 124controls the flow of energy between the Li-ion battery 160 and theultracapacitors 132 to permit current flow only in the direction fromthe Li-ion battery 160 to the ultracapacitors 132.

Further, the first control circuitry 122 is coupled to eachultracapacitor to provide overcharge protection and balancing of thecharge among the ultracapacitors as current flows from the Li-ionbattery 160 to the ultracapacitors 132. For example, in someembodiments, the control circuitry 122 may control the current flow suchthat as the flow from the Li-ion battery 160 reaches each ultracapacitor(from S1 to S6), current is directed first to S1, then to S2 and so on,until the current reaches S6. In this way, when each ultracapacitorreaches its required voltage level, the current from the Li-ion battery160 will bypass that ultracapacitor to balance with the otherultracapacitors in the pack 132. According to other embodiments, othercomponents or devices may be used to balance the charging of theultracapacitors; all such variations are intended to be within the scopeof this disclosure.

Referring to FIG. 13, a combined 24V Pb-acid battery and ultracapacitorsystem 162 for vehicle applications with recharge capability is shownaccording to an exemplary embodiment. The system as shown in FIG. 13includes a battery 164 having a number of cells (or battery units) shownas twelve cells C1-C12 that are connected in series with one another andto terminals T3 (110) and T4 (112), which are connected to thealternator of the vehicle's electrical system for maintaining the chargeon the battery cells (and providing a power source to other electricalloads of the vehicle). An ultracapacitor pack 166 is shown connected inparallel with the battery and has twelve individual ultracapacitorsS1-S12 connected in series with one another and to terminals T1 (116)and T2 (118), which are connected to the engine-starting portion of thevehicle's electrical system for providing relatively short and highcurrent for starting the vehicle. The number of ultracapacitors and thecapacity of the ultracapacitors are selected so that the total voltageof the ultracapacitors substantially matches the total voltage of theseries of cells in the battery. According to the embodiment of FIG. 13,each of the twelve Pb-acid cells has a voltage of approximately 2V, sothat the total voltage of the battery is about 24V. Also, each of thetwelve ultracapacitors has an average voltage of about 1.9V (but may bewithin the range of about 1V-2.8V). Accordingly, twelve ultracapacitorsare selected so that the total voltage approximately matches the voltageof the Pb-acid battery 164.

The system of FIG. 13 also includes the management and control system120 that permits the Pb-acid battery 164 to quickly recharge the twelveultracapacitors following discharge (e.g. engine starts). As before, inthe illustrated embodiment, the management and control system 120includes the first management and control circuitry 122 and the secondmanagement and control circuitry 124. During operation, the managementand control system 120 operates to provide overcharge protection andcharge balance for the ultracapacitors 132. More specifically, duringoperation, the control circuitry 122 and 124 controls the flow of energybetween the Pb-acid battery 164 and the ultracapacitors 166 to permitcurrent flow only in the direction from the Pb-acid battery 164 to theultracapacitors 166.

Further, the first control circuitry 122 is coupled to eachultracapacitor to provide overcharge protection and balancing of thecharge among the ultracapacitors as current flows from the Pb-acidbattery 164 to the ultracapacitors 166. For example, in someembodiments, the control circuitry 122 may control the current flow suchthat as the flow from the Pb-acid battery 164 reaches eachultracapacitor (from S1 to S12), current is directed first to S1, thento S2 and so on, until the current reaches S12. In this way, when eachultracapacitor reaches its required voltage level, the current from thePb-acid battery 164 will bypass that ultracapacitor to balance with theother ultracapacitors in the pack 166. According to other embodiments,other components or devices may be used to balance the charging of theultracapacitors; all such variations are intended to be within the scopeof this disclosure.

Referring to FIG. 14, a combined 26V Li-ion (LiFePO₄/graphite) batteryand ultracapacitor system 170 for vehicle applications with rechargecapability is shown according to a presently disclosed embodiment. Thesystem 170 as shown in FIG. 14 includes a battery 172 having a number ofcells (or battery units) shown as eight cells C1-C8 that are connectedin series with one another and to terminals T3 (110) and T4 (112), whichare connected to the alternator of the vehicle's electrical system formaintaining the charge on the battery cells (and providing a powersource to other electrical loads of the vehicle). The ultracapacitorpack 166 is shown connected in parallel with the battery 172 and hastwelve individual ultracapacitors S1-S12 connected in series with oneanother and to terminals T1 (116) and T2 (118), which are connected tothe engine-starting portion of the vehicle's electrical system forproviding relatively short and high current for starting the vehicle.The number of ultracapacitors and the capacity of the ultracapacitorsare selected so that the total voltage of the ultracapacitorssubstantially matches the total voltage of the series of cells in thebattery. According to the embodiment of FIG. 14, each of the eightLi-ion cells has a voltage of approximately 3.2V, so that the totalvoltage of the battery 172 is about 26V. Also, each of the twelveultracapacitors has an average voltage of about 1.9V (but may be withinthe range of about 1V-2.8V). Accordingly, twelve ultracapacitors areselected so that the total voltage approximately matches the voltage ofthe Li-ion battery.

The system of FIG. 14 also includes the management and control system120 that permits the Li-ion battery 172 to quickly recharge the twelveultracapacitors 166 following discharge (e.g. engine starts). As before,in the illustrated embodiment, the management and control system 120includes the first management and control circuitry 122 and the secondmanagement and control circuitry 124. During operation, the managementand control system 120 operates to provide overcharge protection andcharge balance for the ultracapacitors 166. More specifically, duringoperation, the control circuitry 122 and 124 controls the flow of energybetween the Li-ion battery 172 and the ultracapacitors 166 to permitcurrent flow only in the direction from the Li-ion battery 172 to theultracapacitors 166.

Further, the first control circuitry 122 is coupled to eachultracapacitor to provide overcharge protection and balancing of thecharge among the ultracapacitors as current flows from the Li-ionbattery 172 to the ultracapacitors 166. For example, in someembodiments, the control circuitry 122 may control the current flow suchthat as the flow from the Li-ion battery 172 reaches each ultracapacitor(from S1 to S12), current is directed first to S1, then to S2 and so on,until the current reaches S12. In this way, when each ultracapacitorreaches its required voltage level, the current from the Li-ion battery172 will bypass that ultracapacitor to balance with the otherultracapacitors in the pack 166. According to other embodiments, othercomponents or devices may be used to balance the charging of theultracapacitors; all such variations are intended to be within the scopeof this disclosure.

Referring to FIG. 15, a combined 48V battery and ultracapacitor system174 for vehicle applications with recharge capability is shown accordingto a presently disclosed embodiment. The system 174 as shown in FIG. 15includes a battery 176 having a number of cells (or battery units) shownas cells C1-CY that are connected in series with one another and toterminals T3 (110) and T4 (112), which are connected to the alternatorof the vehicle's electrical system for maintaining the charge on thebattery cells (and providing a power source to other electrical loads ofthe vehicle). An ultracapacitor pack 178 is shown connected in parallelwith the battery 176 and has twelve individual ultracapacitors S1-SXconnected in series with one another and to terminals T1 (116) and T2(118), which are connected to the engine-starting portion of thevehicle's electrical system for providing relatively short and highcurrent for starting the vehicle.

In one embodiment, the battery 176 may be a Pb-acid battery includingcells C1-C24, and the ultracapacitor pack 178 may include betweenapproximately 16 and approximately 30 ultracapacitors. In anotherembodiment, the battery 176 may be a Li-ion battery with LiFePO₄contained positive material including cells C1-C16, and theultracapacitor pack 178 may include between approximately 16 andapproximately 30 ultracapacitors. Further, in another embodiment, thebattery 176 may be a Li-ion battery with LiMn₂O₄ contained positivematerial including cells C1-C13, and the ultracapacitor pack 178 mayinclude between approximately 16 and approximately 30 ultracapacitors.Still further, in another embodiment, the battery 176 may be a Li-ionbattery with LiFePO₄ contained positive material including cells C1-C16,and the ultracapacitor pack 178 may include between approximately 12 andapproximately 24 ultracapacitors, and the ultracapacitors may be hybridultracapacitors with Li intercalation electrodes including a graphitecontained negative electrode.

The system of FIG. 15 also includes the management and control system120 to permit current flow only in the direction from the battery 176 tothe ultracapacitors 178. As before, in the illustrated embodiment, themanagement and control system 120 includes the first management andcontrol circuitry 122 and the second management and control circuitry124. During operation, the management and control system 120 operates toprovide overcharge protection and charge balance for the ultracapacitors178, as described in detail above with respect to FIGS. 8-14.

The above-described features of the management and control systemsassociated with the combined battery and ultracapacitor systems mayprovide a variety of advantages over existing systems. For example, incertain embodiments, the combination of a high energy density batteryand high power ultracapacitor at voltages within a range fromapproximately 24V to approximately 120V may provide advantages for avariety of types of vehicle applications, such as micro-hybrid andmild-hybrid, to improve the fuel efficiency and reduce the CO2 emissionsof such vehicles. As noted above, providing combined battery andultracapacitor systems in the foregoing voltage range may offer avariety of benefits.

More specifically, in certain instances, the size of a Pb-acid batteryfor SLI may be determined by both the cold cranking current at lowtemperatures (a power-related requirement) as well as the electric loadof the vehicle (e.g., lights, electronics, chassis electrifications,etc.), which is an energy-related requirement. Some current Pb-acidbatteries may have an energy density of approximately 40 Wh/kg, acapacity of approximately 70 Ah, and a voltage around 12V. Accordinglysuch batteries may typically supply a cold cranking current around 700Ah at −18° C. In some instances, it may be desirable to improve thedensity of power and energy that energy source systems are capable ofproviding. For example, some mild-hybrid vehicles are equipped with amotor/generator in a parallel configuration allowing the engine to beturned off when the car is coasting, braking, or stopped, yet restartquickly. Accordingly, such demands may require the energy storage devicein such mild hybrid vehicles to have higher power and energy output thannon-hybrid or electric SLI vehicles.

Again, by providing battery and ultracapacitor combination systems atvoltages within a range from approximately 24V to approximately 120V, avariety of advantages may be realized. That is, by combining a varietyof battery types and ultracapacitors into a single system, the benefitsassociated with each technology type may be realized in a single device.In certain embodiments, the Li-ion battery technology may provide anenergy density up to approximately 200 Wh/kg (which may be approximately5 times that of traditional Pb-acid batteries). However, some Li-ionbatteries may have a discharge rate of approximately 2 C at −18° C.,which is lower than the Pb-acid battery cold cranking performance (e.g.,approximately 10 C). Additionally, ultracapacitors or hybridultracapacitors may demonstrate high power density of approximately 10kW/kg at room temperature (or a power density reaching up toapproximately 1 kW/kg at approximately −30° C.). Presently disclosedembodiments of combination energy source systems may combine theadvantages of one or more of these battery types with the advantages ofthe ultracapacitors into a single device. Still further, by providingsystems in the range from approximately 24V to approximately 120V, theresistance heat loss may be reduced at high power output, thus providingadditional advantages over single device systems and systems provided inlower voltage ranges.

To facilitate back-compatibility, retrofitting, battery replacement,physical support and electrical connection, it is presently contemplatedthat the battery and ultracapacitor, and battery-ultracapacitor-controlcircuitry combinations discussed in the present disclosure may bephysically packaged together in an enclosure having a form factor thatconforms to conventional battery packaging. That is, a shell orenclosure may be employed for housing combinations of batteries,ultracapacitors, and, where desired, control circuitry of the typediscussed herein that is similar to or identical to those used withconventional Pb-acid or other battery types. The enclosures may deviatefrom conventional ones in certain respects, or be colored or labeleddifferently to clearly indicate that the replacement includes theseinternal components, although it is contemplated that features such asphysical dimensions useful for placing and securing the devices, such asin vehicle applications, and locations and dimensions of terminals maybe the same as or sufficiently similar to the conventional batteriesthat they replace to permit such replacement with little or noalteration of the existing supports or wiring.

FIG. 21 illustrates an exemplary standard battery enclosure 246 that isinternally configured to house one or more batteries 248 or cells andone or more ultracapacitors 250. Optionally as well, the enclosure maycontain control circuitry 252, regulation circuitry, and so forth,supported on one or multiple circuit boards. The physical dimensions ofthe enclosure may conform to existing standards for the particularbattery type and application that the new battery is intended toreplace. In particular, in the illustration of FIG. 21, the enclosurehas a height 254, a width 256, and a depth 258 that are substantiallythe same as dimensions of a selected standard battery. In this example,the battery terminals 260 are situated in top positions offset from thebattery centerline. FIG. 22 shows another exemplary battery enclosure262 having dimensions that conform and a unique shape that may conformto those of a desired battery that the new assembly and circuitry areintended to replace. In this case, terminals may be located on the topof the enclosure, or on a front side, as indicated by reference numeral264. Moreover, the standard form factors will include mounting orsecurement features, such as holddowns and so forth, as indicatedgenerally by reference numeral N30 in FIGS. 21 and 22.

As will be appreciated by those skilled in the art, certain industrystandards have been developed for use in configuring the physicalpackaging of batteries for many applications. For example, the BatteryCouncil International (BCI) is a trade association that sets certainstandards for vehicle batteries. A number of battery groups and sizeshave been specified by the BCI. The listing below provides examples ofcertain of these:

BCI Typical Maximum Overall Dimensions Group Millimeters Inches Number LW H L W H PASSENGER CAR AND LIGHT COMMERCIAL_BATTERIES 12-VOLT (6 CELLS)21 208 173 222 8 3/16 6 13/16 8¾ 22F 241 175 211 9½ 6⅞ 8 5/16 22HF 241175 229 9½ 6⅞ 9 22NF 240 140 227 9 7/16 5½ 8 15/16 22R 229 175 211 9 6⅞8 5/16 24 260 173 225 10¼ 6 13/16 8⅞ 24F 273 173 229 10¾ 6 13/16 9 24H260 173 238 10¼ 6 13/16 9⅜ 24R 260 173 229 10¼ 6 13/16 9 24T 260 173 24810¼ 6 13/16 9¾ 25 230 175 225 9 1/16 6⅞ 8⅞ 26 208 173 197 8 3/16 6 13/167¾ 26R 208 173 197 8 3/16 6 13/16 7¾ 27 306 173 225 12 1/16 6 13/16 8⅞27F 318 173 227 12½ 6 13/16 8 15/16 27H 298 173 235 11¾ 6 13/16 9¼ 29NF330 140 227 13 5½ 8 15/16 31 325 167 238 12 13/16 6 9/16 9⅜ 31A 325 167238 12 13/16 6 9/16 9⅜ 31T 325 167 238 12 13/16 6 9/16 9⅜ 33 338 173 23813 5/16 6 13/16 9⅜ 34 260 173 200 10¼ 6 13/16 7⅞ 34/78 260 175 200 101/16 6⅞ 7⅞ 34R 260 173 200 10¼ 6 15/16 7⅞ 35 230 175 225 9 1/16 6⅞ 8⅞36R 263 183 206 10⅜ 7¼ 8⅛ 40R 277 175 175 10 15/16 6⅞ 6⅞ 41 293 175 17511 3/16 6⅞ 6⅞ 42 243 173 173 9 5/16 6 13/16 6 13/16 43 334 175 205 13⅛6⅞ 8 1/16 45 240 140 227 9 7/16 5½ 8 15/16 46 273 173 229 10¾ 6 13/16 947 246 175 190 9 11/16 6⅞ 7½ 48 306 175 192 12 1/16 6⅞ 7 9/16 49 381 175192 15 6⅞ 7 3/16 50 343 127 254 13½ 5 10 51 238 129 223 9⅜ 5 1/16 813/16 51R 238 129 223 9⅜ 5 1/16 8 13/16 52 186 147 210 7 5/16 5 13/16 8¼53 330 119 210 13 4 11/16 8¼ 54 186 154 212 7 5/16 6 1/16 8⅜ 55 218 154212 8⅝ 6 1/16 8⅜ 56 254 154 212 10 6 1/16 8⅜ 57 205 183 177 8 1/16 73/16 6 15/16 58 255 183 177 10 1/16 7 3/16 6 15/16 58R 255 183 177 101/16 7 3/16 6 15/16 59 255 193 196 10 1/16 7⅝ 7¾ 60 332 160 225 13 1/166 5/16 8⅞ 61 192 162 225 7 9/16 6⅜ 8⅞ 62 225 162 225 8⅞ 6⅜ 8⅞ 63 258 162225 10 3/16 6⅜ 8⅞ 64 296 162 225 11 11/16 6⅜ 8⅞ 65 306 190 192 12 1/167½ 7 9/16 70 208 179 196 8 3/16 7 1/16 7 11/16 71 208 179 216 8 3/16 71/16 8½ 72 230 179 210 9 1/16 7 1/16 8¼ 73 230 179 216 9 1/16 7 1/16 8½74 260 184 222 10¼ 7¼ 8¾ 75 230 179 196 9 1/16 7 1/16 7 11/16 75/25 238173 197 9⅜ 6 13/16 7¾ 76 334 179 216 13⅛ 7 1/16 8½ 78 260 179 196 10¼ 71/16 7 11/16 85 230 173 203 9 1/16 6 13/16 8 86 230 173 203 9 1/16 613/16 8 90 246 175 175 9 11/16 6⅞ 6⅞ 91 280 175 175 11 6⅞ 6⅞ 92 317 175175 12½ 6⅞ 6⅞ 93 354 175 175 15 6⅞ 6⅞ 95R 394 175 190 15 9/16 6⅞ 7½ 96R242 173 175 9 9/16 6 13/16 6⅞ 97R 252 175 190 9 15/16 6⅞ 7½ 98R 283 175190 11 3/16 6⅞ 7½ PASSENGER CAR AND LIGHT COMMERCIAL BATTERIES 6-VOLT(3CELLS)  1 232 181 238 9⅛ 7⅛ 9⅜  2 264 181 238 10⅜ 7⅛ 9⅜  2E 492 105 23219 7/16 4⅛ 9⅛  2N 254 141 227 10 5 9/16 8 15/16 17HF 187 175 229 7⅜ 6⅞ 9HEAVY-DUTY COMMERCIAL BATTERIES 12-VOLT (6 CELLS)  4D 527 222 250 20¾ 8¾9⅞  6D 527 254 260 20¾ 10 10¼  8D 527 283 250 20¾ 11⅛ 9⅞ 28 261 173 24010 5/16 6 13/16 9 7/16 29H 334 171 232 13⅛ 6¾ 9⅛ 10 30H 343 173 235 13½6 13/16 9¼ 10 31 330 173 240 13 6 13/18 9 7/16 ELECTRIC VEHICLEBATTERIES 6-VOLT (3 CELLS) GC2 264 183 270 10⅜ 7 3/16 10⅝ GC2H 264 183295 10⅜ 7 3/16 11⅝

It should be noted that this listing is not exhaustive, and other formfactors may be utilized. A number of variations in these form factorsmay be due to such factors as rated voltages, capacity, application, thephysical mounting requirements (which may vary for different originalequipment manufacturers), the terminal types and configurations, thecountry or region, and so forth. Terminals may be placed, for example,in top, front, side or a combination of locations. Holddown ledges andfeatures may similarly vary with the different enclosures.

The particular shape and physical configuration of the internal battery,the ultracapacitors, and any included circuitry may be adapted for theinternal space and layout available within the particular enclosures. Itis contemplated that locating and securing structures, isolatingstructures, interconnects and so forth will be adapted within theenclosures or placed in the enclosures during assembly to locate andhold the batteries, ultracapacitors and any related circuitry in place,and to interconnect these as required for their proper electricalfunction. Many variations of such structures may be designed, and theirparticular configurations are considered to be within the ability ofthose skilled in the art without undue experimentation.

It should also be noted that the particular battery, ultracapacitors andany included circuitry may be of any desired type, rating, size and soforth, such as those described above. It is presently contemplated thatthe battery systems thus provided may be different, but in many or mostcases will be such as to permit retrofitting of existing conventionalbatteries, such as Pb-acid batteries, glass mat batteries, and so forth.For original equipment manufacturers, such as vehicle manufacturers, thenew battery systems may be installed as original equipment in the placeof conventional batteries with little or no alteration in the locationor physical configuration of support structures and electricalconnections. The battery systems may thus be used in connection withconventional internal combustion engines, hybrid vehicles, electricvehicles, and forth. Moreover, the battery systems may be used fornon-vehicular applications, such as for home or building energy storage,energy generation systems (e.g., wind or engine generators) and soforth.

It should also be noted that in certain implementations, the systemenclosure may be made somewhat smaller than the standard dimensions forexisting batteries, and various adapters, shims, and so forth may beused to more closely conform to existing mounting structures. Suchadapters and similar hardware may be obtained in kits, sold separatelyor with the battery systems, and may be designed to allow the batterysystems to fit within particular models or families of vehicles. Asnoted above, such adapters and hardware may also allow for the use ofenclosures of irregular or non-standard shapes. Certain of theseadapters are illustrated in FIG. 22, and labeled generally “A”. Thesemay fit on sides, the base, the top, or generally anywhere on theenclosure that may not directly conform with the desired mountingposition or structures. Additional information regarding BCI batterystandards, technical specifications and replacement is available in theBCI Battery Technical Manual and the BCI Battery Replacement Data Book,both available from BCI of Chicago, Ill.

It should further be noted that a variety of other circuits notillustrated herein may be provided and utilized in an energy sourcedevice in accordance with presently disclosed embodiments. For example,in certain embodiments, the energy source system 10 may include multiplebattery packs, as described in detail in U.S. Provisional PatentApplication No. 61/477,730, entitled “Multiple Battery System forVehicle Applications,” filed Apr. 21, 2011, which is hereby incorporatedby reference. For example, in one embodiment, the energy source system10 may include a first battery pack configured to provide electricalpower to an engine starting system of a vehicle and a second batterypack configured to provide electrical power to at least one electronicsystem of the vehicle. Further, the battery packs may, for example, becontrolled by a suitable controller, such as controller 26, and thebattery packs may be provided in addition to or in place of thebatteries and/or ultracapacitor systems disclosed herein, depending on avariety of implementation-specific parameters.

Still further, as shown in the embodiment of FIG. 16, an energy sourcesystem 180 includes a differential state of charge (SOC) energy storagedevice 182 having a housing 184 that encloses a low SOC energy storagedevice 186 and a high SOC energy storage device 188 in a singleenclosure. In certain embodiments, the energy storage devices may be anycombination of devices capable of storing energy and/or charge. Forexample, in some embodiments, the energy storage devices may include butare not limited to capacitors, ultracapacitors, a capacitive electrodecoupled to or contained within an energy storage device, electrochemicalstorage devices (e.g., lithium-based batteries, nickel-based batteries,lead-based batteries, etc.), fuel cells, or any other suitable materialor device capable of storing energy.

As illustrated in FIG. 16, the low SOC device 186 includes a negativeterminal 190 coupled to ground 192 and a positive terminal 193 that iscoupled to the device output 194. Similarly, the high SOC device 188includes a negative terminal 196 coupled to ground 198 and a positiveterminal 200 that is coupled to the device output 194. By combining therelatively low SOC device 186 with the relatively high state of chargedevice 188 in the housing 184, the charge acceptance and charging rateof the differential SOC device 182 may be improved compared to singleSOC devices, as described in more detail below.

It should be noted that the low SOC device 186 and the high SOC devicemay be any suitable devices that have different states of chargerelative to one another. For example, in one embodiment, the low SOCdevice may be a battery type that operates at approximately 30% SOC, andthe high SOC device may be a battery type that operates at approximately80% SOC. In some embodiments, the low SOC device and/or the high SOCdevice may be a Li-ion battery, an ultracapacitor, a Pb-acid battery orany combination or sub-combination of the foregoing devices.

An example of a voltage versus SOC plot 202 for two such example devicesis shown in FIG. 17. As shown, the plot 202 includes a voltage axis 204and a percentage SOC axis 206. The plot 202 further includes a curve 208corresponding to the operational profile of the low SOC device 186 and aplot 210 corresponding to the operational profile of the high SOC device188. It should be noted that the differences between the curves 208 and210 may be attributed, for example, to the operational differencesbetween battery types. For instance, in one embodiment, the curves 208and 210 may correspond to two different Li-ion batteries, each having adifferent voltage due to a different battery chemistry, anode material,cathode material, or any other parameter of the battery.

For further example, FIG. 18 illustrates a voltage versus SOC plot 212for two example devices having different battery chemistries.Specifically, the plot 212 includes a curve 214 corresponding to theoperational profile of the low SOC device 186 and a plot 216corresponding to the operational profile of the high SOC device 188. Inthis embodiment, the low SOC device may, for example, be a Li-ionbattery, and the high SOC device may, for example, by a Pb-acid battery.Here again, the differences between the curves 214 and 216 may beattributed, for example, to the differences in battery chemistry betweenthe devices 186 and 188.

During operation, the combination of the low SOC device 186 and the highSOC device 188 may offer a variety of performance benefits as comparedto single SOC systems or as compared to systems in which the single SOCdevice is scaled to a larger size and capability. For example, incertain embodiments, the low SOC device 186 may be charged at a higherrate than the high SOC device 188, thus offering advantages, forexample, during regenerative breaking of a vehicle when the high powercharging and charge acceptance of the low SOC device 186 may offset therelatively low charge acceptance of the high SOC device 188.Accordingly, a smaller overall housing 182 may be provided to house adifferential SOC device as compared to a single SOC device having thesame performance abilities with respect to capturing the regenerativeenergy during braking. The foregoing feature may be realized, forexample, in an embodiment in which a Li-ion battery and a Pb-acidbattery are combined into a single differential SOC device.

These and other advantages of the differential SOC device 182 may bebetter understood by considering the plots 218 and 220 illustrated inFIGS. 19 and 20. Specifically, the plot 218 illustrated in FIG. 19includes a charging power capability axis 221 and a voltage axis 222.The plot 218 further includes a main battery plot 224, an auxiliarybattery plot 226, an increased size battery plot 228, and a differentialSOC combination plot 230. As shown in FIG. 19, a distance 232 betweenthe phantom larger size curve 228 and the differential SOC combinationplot 230 visually illustrates the advantage in charging power capabilitythat may be gained by combining the low SOC device 186 and the high SOCdevice 188 in the housing 182, as opposed to scaling up the size andcapability of a single SOC device. Again, a variety of benefits may begained from combining the devices 186 and 188 into the housing 184, suchas an improved charging capability when the device 182 is approximatelyfull.

The plot 220 illustrated in FIG. 20 includes the charging powercapability axis 221 and a SOC axis 234. The plot 220 further includes amain battery plot 236, an auxiliary battery plot 238, an increased sizebattery plot 240, and a differential SOC combination plot 242. As shownin FIG. 20, a distance 244 between the phantom larger size curve 240 andthe differential SOC combination plot 242 visually illustrates theadvantage in charging power capability that may be gained by combiningthe low SOC device 186 and the high SOC device 188 in the housing 182,as opposed to scaling up the size and capability of a single SOC device.Here again, it can be seen that various advantages may be gained fromcombining the devices 186 and 188 into the housing 184.

According to the various exemplary embodiments, a combined battery andultracapacitor system is provided for use in a wide variety of vehicleapplications to provide a number of advantages. The parallelconfiguration of the ultracapacitors provides the necessary shortduration and high capacity discharge necessary to meet the cold crankingcurrent requirements of the vehicle. Also, the system permits the use ofvarious battery technologies for storing and supplying the electricityneeded for other electrical loads of the vehicle and stabilizing theelectrical system voltage level during engine starts, which reduces theweight and size constraints imposed by many conventional vehicle batteryand electrical systems. Further, the system permits utilizing the highpower charge rate of the ultracapacitors to restore the energy duringbraking or stopping (e.g. regenerative braking). Additionally, as notedabove, the battery and ultracapacitors may contain suitable managementsystems to monitor the parameters including temperature, current, andvoltage to prevent them from deep-charging and discharging. Accordingly,all such variations are intended to be within the scope of thisdisclosure.

The various combined battery and ultracapacitor systems provided hereinare adaptable and scalable to fit a wide variety of applications,including start/stop, micro-hybrid, and electric vehicle applications,and to suit a wide variety of voltage requirements. For example, in oneembodiment, as shown in FIG. 23, a vehicle 270 in the form of anautomobile (e.g., a car) having a battery module or system 272 forproviding all or a portion of the motive power for the vehicle 270. Insome embodiments, the vehicle 270 may be an electric vehicle (EV), ahybrid electric vehicle (HEV), a plug-in hybrid electric vehicle (PHEV),or any other type of vehicle using electric power for propulsion(collectively referred to as “electric vehicles”). Additionally,although illustrated as a car in FIG. 23, the type of the vehicle 270may be implementation-specific, and, accordingly, may differ in otherembodiments, all of which are intended to fall within the scope of thepresent disclosure. For example, the vehicle 270 may be a truck, bus,industrial vehicle, motorcycle, recreational vehicle, boat, or any othertype of vehicle that may benefit from the use of electric power for allor a portion of its propulsion power.

Further, although the battery module 272 is illustrated in FIG. 23 asbeing positioned in the trunk or rear of the vehicle 270, according toother exemplary embodiments, the location of the battery module 272 maydiffer. For example, the position of the battery module 272 may beselected based on the available space within the vehicle 270, thedesired weight balance of the vehicle 270, the location of othercomponents used with the battery system (e.g., battery managementsystems, vents or cooling devices, etc.), and a variety of otherimplementation-specific considerations.

FIG. 24 illustrates a cutaway schematic view of the vehicle 270 providedin the form of an HEV according to a presently disclosed embodiment. Inthe illustrated embodiment, the battery module or system 272 is providedtoward the rear of the vehicle 270 proximate a fuel tank 274. However,in other embodiments, the battery module 272 may be provided immediatelyadjacent the fuel tank 274 or may be provided in a separate compartmentin the rear of the vehicle 270 (e.g., a trunk) or may be providedelsewhere in the vehicle 270. An internal combustion engine 276 isprovided for times when the HEV utilizes gasoline power to propel thevehicle 270. An electric motor 278, a power split device 280, and agenerator 282 are also provided as part of the vehicle drive system.Such an HEV may be powered or driven by just the battery system 272, byjust the engine 276, or by both the battery system 272 and the engine276. It should be noted that other types of vehicles and configurationsfor the vehicle electrical system may be used according to otherembodiments, and that the schematic illustration of FIG. 24 should notbe considered to limit the scope of the subject matter described in thepresent application. Indeed, according to various other embodiments, thesize, shape, and location of the battery module or system 272, the typeof vehicle 270, the type of vehicle technology (e.g., EV, HEV, PHEV,etc.), and the battery chemistry, among other features, may differ fromthose shown or described.

According to an embodiment, the battery module or system 272 isresponsible for packaging or containing electrochemical cells orbatteries, connecting the electrochemical cells to each other and/or toother components of the vehicle electrical system, and regulating theelectrochemical cells and other features of the battery system 272. Forexample, the battery module or system 272 may include features that areresponsible for monitoring and controlling the electrical performance ofthe system, managing the thermal behavior of the system, containmentand/or routing of effluent (e.g., gases that may be vented from abattery cell), and other aspects of the battery module or system.

Here again, it should also be noted that the present techniques alsoapply to storage and use of energy in vehicles that do not use orsometimes use electrical energy for propulsion. For example, suchvehicles may include conventional internal combustion engines used forpropulsion, or vehicles that may employ regenerative braking, but notuse the resulting energy directly for propulsion. Moreover, thetechniques may be particularly advantageous in any vehicle in certainuse cases. For example, in so-called stop-start applications the vehicleengine or prime mover may be shut off at certain times (e.g., whenstopped at an intersection) and restarted each time, resulting in a needfor starting energy. Finally, it should be noted that the techniques maybe advantageous for any of a range of cases both vehicular andnon-vehicular, such as for driving accessories, electrical loads, and soforth.

As utilized herein, the terms “approximately,” “about,” “substantially,”and similar terms are intended to have a broad meaning in harmony withthe common and accepted usage by those of ordinary skill in the art towhich the subject matter of this disclosure pertains. It should beunderstood by those of skill in the art who review this disclosure thatthese terms are intended to allow a description of certain featuresdescribed and claimed without restricting the scope of these features tothe precise numerical ranges provided. Accordingly, these terms shouldbe interpreted as indicating that insubstantial or inconsequentialmodifications or alterations of the subject matter described and claimedare considered to be within the scope of the invention as recited in theappended claims.

It should be noted that the term “exemplary” as used herein to describevarious embodiments is intended to indicate that such embodiments arepossible examples, representations, and/or illustrations of possibleembodiments (and such term is not intended to connote that suchembodiments are necessarily extraordinary or superlative examples).

The terms “coupled,” “connected,” and the like as used herein mean thejoining of two members directly or indirectly to one another. Suchjoining may be stationary (e.g., permanent) or moveable (e.g., removableor releasable). Such joining may be achieved with the two members or thetwo members and any additional intermediate members being integrallyformed as a single unitary body with one another or with the two membersor the two members and any additional intermediate members beingattached to one another.

It should be noted that the orientation of various elements may differaccording to other exemplary embodiments, and that such variations areintended to be encompassed by the present disclosure.

It is also important to note that the construction and arrangement ofthe combined battery and ultracapacitor systems for vehicle applicationsas shown in the various exemplary embodiments is illustrative only.Although only a few embodiments of the present inventions have beendescribed in detail in this disclosure, those skilled in the art whoreview this disclosure will readily appreciate that many modificationsare possible (e.g., variations in battery chemistry and material,quantities and capacities, selection of ultracapacitor size andcapacity, etc.) without materially departing from the novel teachingsand advantages of the subject matter disclosed herein. For example, thebattery technologies may include any one or more of Li-ion, Pb-acid,Ni-M(H), Ni—Zn, or other battery technologies. Further, the balancing ofthe charge to the ultracapacitors may be accomplished by other suitableelectronic components. Accordingly, all such modifications are intendedto be included within the scope of the present invention as defined inthe appended claims. The order or sequence of any process or methodsteps may be varied or re-sequenced according to alternativeembodiments. Other substitutions, modifications, changes and omissionsmay be made in the design, operating conditions and arrangement of thevarious exemplary embodiments without departing from the scope of thepresent inventions.

The invention claimed is:
 1. An energy source system, comprising: abattery comprising one or more electrochemical cells coupled in serieswith one another; an ultracapacitor; a first switching device coupled tothe battery and configured to selectively connect and disconnect thebattery to a load; a second switching device coupled to theultracapacitor and configured to selectively connect and disconnect theultracapacitor to the load; a direct current to direct current (DC-DC)converter configured to electrically couple the battery to theultracapacitor; a sensing system configured to sense an operationalparameter of the battery, an operational parameter of theultracapacitor, and a load parameter; and a controller coupled to thefirst switching device, the second switching device, and the DC-DCconverter and configured to: detect a first engine start signal;determine, upon detecting the first engine start signal and based on thesensed operational and load parameters, whether energy stored in thebattery is sufficient to start an internal combustion engine associatedwith an electromechanical vehicle; determine, based on the sensedoperational and load parameters, a desired energy flow between thebattery, the ultracapacitor, the DC-DC converter, and the load when theenergy stored in the battery is not sufficient to start the internalcombustion engine; and control the first switching device, the secondswitching device, and the DC-DC converter to achieve the determinedenergy flow, such that the ultracapacitor is charged to a statesufficient to start the internal combustion engine during a time lapsebetween receiving the first engine start signal and receiving a secondengine start signal, and wherein the ultracapcitor is coupled to theload in place of the battery via the second switching device.
 2. Thesystem of claim 1, wherein the load comprises a starting load from theinternal combustion engine of the electromechanical vehicle.
 3. Thesystem of claim 2, wherein the controller is configured to control theDC-DC converter to transfer energy from the battery to theultracapacitor when the operational parameter of the battery indicatesthat the battery does not have enough stored energy to meet the startingload.
 4. The system of claim 3, wherein the controller is configured tocontrol the second switching device to couple the ultracapacitor to theload to meet the starting load.
 5. The system of claim 1, wherein thefirst switching device comprises a field-effect transistor configured toconnect and disconnect the battery to the load in a variable manner. 6.The system of claim 1, wherein the second switching device comprises afield-effect transistor configured to connect and disconnect theultracapacitor to the load in a variable manner.
 7. The system of claim1, wherein the battery comprises a Pb-acid battery.
 8. The system ofclaim 1, wherein the battery comprises a Ni-M(H) battery.
 9. The systemof claim 1, wherein the battery comprises a Ni-Zn battery.
 10. Thesystem of claim 1, wherein the operational parameter of the batterycomprises the voltage of the battery, the operational parameter of theultracapacitor comprises the voltage of the ultracapacitor, and the loadparameter comprises the load voltage.
 11. The energy source system ofclaim 1, wherein the energy source system is disposed within a singlehousing.
 12. The energy storage system of claim 1, such that receivingthe second engine start signal comprises the controller allowing thesecond engine start signal to be received upon the ultracapacitor beingcharged to the sufficient state to start the internal combustion engine.13. A method for controlling an energy source system, comprising:receiving a first engine start signal; determining, upon receiving thefirst engine start signal and based on a received input, whether energystored in a battery is sufficient to start an internal combustion engineassociated with an electromechanical vehicle; controlling a directcurrent to direct current (DC-DC) converter to transfer energy from thebattery to an ultracapacitor when the energy stored in the battery isnot sufficient to start the internal combustion engine, wherein theultracapacitor is charged to a state sufficient to start the internalcombustion engine during a time lapse between receiving the first enginestart signal and receiving a second engine start signal; and controllinga switch coupled to the ultracapacitor to electrically couple theultracapacitor to the internal combustion engine to enable a first flowof energy from the ultracapacitor to the internal combustion engine tostart the internal combustion engine in place of a second flow of energyfrom the battery to the internal combustion engine when the energystored in the battery is not sufficient to start the internal combustionengine.
 14. The method of claim 13, wherein the battery comprises aPb-acid battery.
 15. The method of claim 13, wherein the batterycomprises a Li-ion battery.
 16. The method of claim 13, wherein thebattery comprises a Ni-M (H) battery.
 17. The method of claim 13,wherein the battery comprises a Ni-Zn battery.
 18. The method of claim13, comprising controlling a second switch coupled to the battery toelectrically couple the battery to the internal combustion engine toenable the second flow of energy from the battery to the internalcombustion engine to start the internal combustion engine when theenergy stored in the battery is sufficient to start the internalcombustion engine.
 19. A controller for an energy source system having aplurality of energy storage devices, configured to: receive a firstengine start signal; determine, upon receiving the first engine startsignal and based on a received input, whether energy stored in a batteryis sufficient to start an internal combustion engine associated with anelectromechanical vehicle; control a direct current to direct current(DC-DC) converter to transfer energy from the battery to anultracapacitor when the energy stored in the battery is not sufficientto start the internal combustion engine, such that the ultracapacitor ischarged to a state sufficient to start the internal combustion engineduring a time lapse between receiving the first engine start signal andreceiving a second engine start signal; and control a first switchcoupled to the ultracapacitor to electrically couple the ultracapacitorto the internal combustion engine to enable a first flow of energy fromthe ultracapacitor to the internal combustion engine to start theinternal combustion engine in place of a second flow of energy from thebattery to the internal combustion engine when the energy stored in thebattery is not sufficient to start the internal combustion engine. 20.The controller of claim 19, configured to control a second switchcoupled to the battery to electrically couple the battery to theinternal combustion engine to enable a flow of energy from the batteryto the internal combustion engine to start the internal combustionenergy when the energy stored in the battery is sufficient to start theinternal combustion engine.